The present invention relates to a printing apparatus and a method of carrying out various printing functions. Although many applications for the invention may be possible, the disclosure herein emphasizes the application to ware decoration. It should be understood that articles of many types may be printed or decorated using the apparatus and method of the present invention and such applications are part of the invention herein.
In multicolor ware decoration, speed, versatility, ease of setup, quality of reproduction, accuracy of registration, and cost effectiveness are important factors to consider. State of the art decorating devices approach some but not all of the above factors satisfactorily. The present invention was developed for various reasons including a desire to both take advantage of the latest ink and elastomer technology and to maximize printing rates without sacrifice of registration.
The machine configuration of the present invention makes use of two geometric relationships illustrated in FIGS. 1-3. First, a cone when placed on the flat surface and rolled, will trace an arc centered along a center line of the arc at the same point as the apex of the cone. The cone will travel along this path freely with no slipping between the surfaces. Second, two cones sharing the same apex and placed side by side will roll one on the other without slipping along a line of contact or common ray of the cones. By choosing the proper ratio of circumferences between the first mentioned cone and the arc traced in the plane of the flat surface, the cone will roll an integral number of revolutions as it travels one revolution about the traced arc. Similarly the proper choice of circumference ratios of cones will produce integral rotations with each other and the arc. Therefore, discrete locations of the cone will always match up with discrete locations along the arc in the flat surface. Accordingly, a special case of synchronous motion may be defined.
The two cones and the flat surface may be driven in synchronism by a proper gearing arrangement, from which a device may be produced which will establish pattern registration from one set of cones to another and the surface as hereinafter illustrated.
The present invention provides means incorporating a working surface lying in a surface complimentary with the cone, adapted to engage the same, and provide a self aligning doctoring device requiring little or no adjustment. An additional feature of the present invention includes a simple ink circulating system taking advantage of the self aligning feature. The device herein described may be adapted for printing multicolor designs on flat, hollow, and other odd shaped ware inside or out, with high quality, high speed, and simplified set up for each of the various types of ware to be decorated with a degree of versatility not heretofore available in the prior art.
In a series of related U.S. patent application Ser. Nos. 332,722; 332,723; 332,725 and 332,726 filed this same date and assigned to the assignee herein, various apparatus and sub-combinations therefor useful with the present invention are disclosed in detail. It should be understood that, to the extent necessary, the teachings of said applications should be considered incorporated by reference herein.